Medical experts are hailing what they describe as 'unprecedentedly strong responses' to a new cancer injection that succeeded in eradicating entire tumours in patients who had previously been resistant to other forms of treatment. The international study, led by London's Institute of Cancer Research (ICR), showed that tumours shrank in 42 per cent of participants.
Breakthrough Treatment for Resistant Cancers
The drug, known as amivantamab, was administered to individuals suffering from recurrent or metastatic head and neck cancer that had ceased to respond to standard treatments. Unlike many cancer medications that require intravenous drips, amivantamab is delivered as a small injection, making it more convenient for patients and easier to administer in outpatient clinics.
One participant, Carl Walsh, a 56-year-old from Birmingham diagnosed with tongue cancer in May 2024, joined the study at The Royal Marsden in July 2025 after chemotherapy and immunotherapy proved unsuccessful. In a statement released during his 17th treatment cycle, Walsh reported significant improvements: 'I now feel able to live a normal life. Before starting the trial, I struggled to speak properly and found eating difficult because of the swelling and pain. Since beginning treatment, the swelling has reduced significantly, and my pain levels have improved considerably. I'm also no longer experiencing the same life-impacting side effects that I had during chemotherapy.'
Unprecedented Response Rates
Professor Kevin Harrington, professor of biological cancer therapies at the ICR and consultant oncologist at The Royal Marsden NHS Foundation Trust, expressed his astonishment at the results. 'These are unprecedentedly strong responses in patients whose disease has become resistant to both chemotherapy and immunotherapy. This is a group of patients for whom treatment options are extremely limited, so seeing this level of benefit is very striking.' He added that the treatment 'has the potential to benefit many thousands of patients each year.'
Head and neck cancer ranks as the sixth most common cancer globally, affecting approximately 12,800 people annually in the UK alone. This phase of the OrigAMI-4 trial involved 102 individuals with recurrent or metastatic head and neck squamous cell carcinoma (HNSCC), whose cancer had continued to progress despite prior immunotherapy and platinum-based chemotherapy. The patients, drawn from 55 hospitals across 11 countries, received only amivantamab, which is being developed by Johnson & Johnson.
Detailed Trial Findings
The results were striking: tumours shrank in 43 participants, with 15 experiencing complete disappearance of their tumours and 28 seeing significant shrinkage. Patients treated with amivantamab lived for a median of 12.5 months after starting treatment, despite having a cancer type with 'very poor outcomes' once standard treatments cease to work, according to the ICR. Tumours began responding within approximately six weeks, and patients had a median of just over six-and-a-half months before the cancer resumed growth.
Mechanism of Action
Amivantamab is classified as a bispecific monoclonal antibody. It works by blocking two signals: EGFR (Epidermal Growth Factor Receptor), a protein that promotes tumour growth, and MET, a separate pathway often exploited by cancer cells to evade treatment. Additionally, the drug has a third benefit: it helps activate the immune system to attack the tumour. The injection is administered every three weeks, and side effects were reported as mild to moderate, with fewer than ten patients discontinuing treatment due to adverse effects.
Expert Commentary and Future Implications
Professor Kristian Helin, chief executive of the ICR, commented on the significance of the study: 'This study demonstrates how the development of new treatments through rigorous cancer research may lead to meaningful advances, even for patients with very limited treatment options. Achieving this level of tumour response and encouraging survival outcomes in such a challenging to treat group represents a significant step forward.'
Amivantamab has already received approval for multiple subtypes of lung cancer across various lines of therapy. The study excluded patients with human papillomavirus (HPV) positive oropharyngeal squamous cell carcinoma, as head and neck cancers not caused by HPV are typically harder to treat and have poorer responses to standard therapy. The ICR emphasised that 'making progress in this group is particularly important.'
The findings are set to be presented at the American Society of Clinical Oncology on Sunday, marking a potential milestone in cancer treatment.
